Internal combustion piston engines are widely used making use of various liquid and gaseous fuels. The variety of fuels has an increasing tendency at least partly due to the diminishing resources of petroleum.
Naturally the fuel which is used in an internal combustion piston engine sets technical requirements to the fuel section in order to operate as desired. Following publications are cited as examples of different fuel sections in connection with an internal combustion engines.
WO2013127526 A1 discloses a power plant include an internal combustion engine adapted to be operated with pyrolysis oil based fuels. The power plant may allow switching fuels while continuously operating internal combustion engine and provide for a stop and start-up procedure for operating the internal combustion engine with pyrolysis oil based fuels.
WO2008065238 A1 shows a marine vessel machinery, comprising a fuel feeding system for feeding fuel to the at least two combustion units, a separate first fuel tank for first fuel and a second fuel tank for second fuel. The fuel feeding system is provided with a fuel blending unit connected to the first and the second fuel tanks.
In US2014109866 A1 there is shown an internal combustion engine includes one main combustion chamber for the combustion of a first combustion mixture, one pre-combustion chamber for each respective main combustion chamber for the combustion of a second combustion mixture, a first fuel gas mixer for providing the first combustion mixture, a second fuel gas mixer for providing the second combustion mixture, an air feed line and a synthesis gas feed line, a first mixture line connected to the first fuel gas mixer and the main combustion chamber, and a second mixture line connected to the second fuel gas mixer and the pre-combustion chamber. The first fuel gas mixer is connected to the synthesis gas feed line for the admixing of synthesis gas, and an open or closed loop control device is provided for open or closed loop controlling mixing ratios of fuel, air and synthesis gas in the first combustion mixture and/or second combustion mixture.
Due to many reasons, but particularly because constantly restricting emission requirements, the variety of potentially usable fuels in an internal combustion piston engine has recently increased. So far it has been a common practise that gaseous fuels have been combusted in piston engines in gaseous form even if they would be stored or delivered in liquefied form. This is suitable and convenient for certain gases, such as natural gas, pure propane or liquefied petroleum gas.
However, there is a need to develop a fuel system for and method of operating an internal combustion engine with certain hydrocarbons compounds which would possible be otherwise wasted.
An object of the invention is to provide a fuel system for and method of operating an internal combustion engine by means of which particularly a gas condensate fuel consisting of hydrocarbon with ≧3 carbon atoms may be efficiently combusted.
It is also an object of the invention to provide a method of processing raw gas comprising one or more steps of processing the raw gas in which the performance is considerably improved compared to the prior art solutions.